/**
 * Created by zengyw on 2014/8/11.
 */
define(['./module'],
    function (directives) {
        directives.directive('datatable', function () {
            return {
                restrict: 'A',

                link: function ($scope, $elem, attrs) {
                    // Start with the defaults. Change this to your defaults.
                    var options = {};

                    // If dtOptions is defined in the controller, extend our default option.
                    if (typeof $scope.dtOptions !== 'undefined') {

                        angular.extend(options, $scope.dtOptions);
                    }

                    // If dtoptions is not declared, check the other options
                    if (attrs['dtoptions'] === undefined) {

                        // Get the attributes, put it in an options
                        // We need to do a switch/case because attributes does not retain case
                        // and datatables options are case sensitive. Damn. It's okay! We need to detect
                        // the callbacks anyway and call it as functions, so it works out!
                        // I put what I needed, most of my settings are not dynamics except those 2.
                        for (property in attrs) {
                            switch (property) {
                                // This is the ajax source
                                case 'sajaxsource':
                                    options['sAjaxSource'] = attrs[property];
                                    break;
                                // This is the ajax data prop. For example, your result might be
                                // {code: 200, data: [ .. ]} -> in the case, sAjaxDataProp is data
                                case 'sajaxdataprop':
                                    options['sAjaxDataProp'] = attrs[property];
                                    break;
                            }
                        }
                    } else {
                        // If dtoptions is declare, extend the current options with it.

                        angular.extend(options, $scope.dtOptions);
                    }

                    // Just some basic validation.
                    if (typeof options['sAjaxSource'] === 'undefined') {

                        throw "Ajax Source not defined! Use sajaxsource='/api/v1/blabla'";
                    }

                    // for Angular http inceptors
                    if (typeof options['fnServerData'] === 'undefined') {
                        options['fnServerData'] = function (sSource, aoData, resultCb) {
                            $http.get(sSource, aoData).then(function (result) {
                                resultCb(result.data);
                            });
                        };
                    }
                    // Get the column options, put it in a aocolumn object.
                    // Obviously, mdata is the only one required.
                    // I personally just needed those 3, if you need other more feel free to add it.
                    // mData also accepts a function; I'm sure there's a more elegant way but for now
                    // it detects if it's a function, and if it is, do it.
                    options.aoColumns = [];

                    // Get the thead rows.
                    $elem.find('thead th').each(function () {
                        var colattr = angular.element(this).data();
                        // Detects if it's a function. Must exist in scope.
                        if (colattr.mdata.indexOf("()") > 1) {

                            // Simple one-liner that removes the ending ()
                            var fn = $scope[colattr.mdata.substring(0, colattr.mdata.length - 2)];

                            // Throw an error if it's not a function.
                            if (typeof fn === 'function') {
                                options.aoColumns.push({
                                    mData: fn,
                                    sClass: colattr.sclass,
                                    bVisible: colattr.bvisible,
                                    mRender: colattr.mrender
                                });

                            } else {

                                throw "mData function does not exist in $scope.";

                            }
                        } else {
                            options.aoColumns.push({
                                mData: colattr.mdata,
                                sClass: colattr.sclass,
                                bVisible: colattr.bvisible,
                                mRender: colattr.mrender
                            });

                        }
                    });

                    //加载datatable数据
                    $elem.dataTable(options);
                }
            }

        });
    }
);